Understeer

[VBAll]

Im getting pretty bad understeer in my r33 and was wondering what might be causing this?

The car has coilovers and is running 235/40/18 tyres

I thought being a rwd it would typically oversteer?

Anyone got any ideas what is causing this and how i might fix it? Would sway bars help?

[salad]

Need a lot more info.

Where are you gettin understeer? Entry, mid corner or exit?

What is your current set up?

What spring rates, swaybars, wheel alignment?

[VBAll]

Its upon exit that i get the understeer mainly.

No sway bars and unsure of the spring rates as i only just bought the car, is there any way for me to find out what they are?

[blind_elk]

What tyre pressure? Fronts should be couple of psi higher than rears. And a stiffer REAR bar might help.

[MrStabby]

This looks pretty cool to me - check it out;

http://www.wtrscca.org/tech.htm

[Kinks]

I can vouch for a 100% standard skyline (springs shocks wheels everything) being very neutral in handling. it will eventually understeer if you overcook it enough into a corner (I generally try not to! heh), and in-corner you can manage the attitude beautifully using the throttle. poke it enough and the back will certainly come out but I don't play with that on the street.

You need to look at your setup and see what has changed from standard. Handling is generally a case of "soften the end you want to grip" so maybe your front coilovers are too stiff, or you have a big sway bar up front. I assume your tyres are the same all round.

[MBS206]

What model tyres do you have?

And if you're easing the throttle on as you exit the corner, generally the car will want to understeer. You just transferred all the weight to the rear wheels, so they're seeing a shitload of available grip, but the front end is left going "Where's my weight?"

If you're punching it out of a corner (From like 0% throttle to 100% throttle) and understeering, get into drag racing, you have ALOT of grip in the rear.

But, when people say to put sway bars on, personally, I'd rather take them off.

A swaybar literally FIGHTS the action of the suspension and putting a rear sway bar on, gives you more front grip, is a total crock, it actually just removes the level of grip from the rear, making the front feel grippier.

Set your spring rates and shock rates. Get it handling how you want, and then for MINOR tweaks, use sway bars (But don't go massive bars)

I've seen this written by numerous people who set up suspension when they raced, and also my wheel aligner nearly kicked me out of his workshop when I mentioned sway bars for the exact same reason.

[Greg]

I found adding castor almost eliminated understeer. I'm selling my car though so I have some rods for sale here http://www.skylinesaustralia.com/forums/in...howtopic=167693

[djr81]

Its upon exit that i get the understeer mainly.

No sway bars and unsure of the spring rates as i only just bought the car, is there any way for me to find out what they are?

I say this without knowing anything about your car and/or driving experience. So please don't flame me if I have this all wrong.

A common mistake people make is to try to carry too much speed across the apex of the turn & hence run out of road on the exit. They then start on about understeer.

Try a bit slower in fast out & make sure you are on the loud pedal as the apex slips by.

[tacker]

I found these upper control arm with neg 5 deg camber made a big difference to understeer. Would not like to have them on the road though you would go through a few sets of fronts

[r33_racer]

yeh no sway bars ftw. I know everytime id want to change suspension settings when i change tyres and tracks id rather run stupidly stiff springs and just change them everytime at the track rather then play with sway bar settings. Chances are if you run with no sway bars you will suffer from alot more body roll, which can help to some degree but will more then likely be a problem. If your pushing it too hard through the corners with minimal camber and castor the tyre is probably running on the outside edge of the tyre and thats why its understeering....but its probably a combo of things if the car isnt setup well.

[djr81]

I found these upper control arm with neg 5 deg camber made a big difference to understeer. Would not like to have them on the road though you would go through a few sets of fronts

Can you please provide some more info on the control arms - ie what brand/where did they come from etc?

[djr81]

yeh no sway bars ftw. I know everytime id want to change suspension settings when i change tyres and tracks id rather run stupidly stiff springs and just change them everytime at the track rather then play with sway bar settings. Chances are if you run with no sway bars you will suffer from alot more body roll, which can help to some degree but will more then likely be a problem. If your pushing it too hard through the corners with minimal camber and castor the tyre is probably running on the outside edge of the tyre and thats why its understeering....but its probably a combo of things if the car isnt setup well.

I don't think he means he has no sway bars currently - I think he means would aftermarket ones help?

The answer to that is - a bit, but not as much as you would think.

[Roy]

When does it understeer? At the track? Which corners at which track? Seriously. If its understeering on the street disconnet a few coil packs so that you are not going that quick through corners. Going to sound harsh but it could be anything, suspension, tyres, alignment or just how you are driving it....lol liek me turning in way too early then wondering why you are pushing on exit. But again if you are getting understeer on the streets, then for gods sake back off a little. A bump in the road, a change of surface, some dirt near a gutter....it wont take much to suck you in and do some damage.

Ouch..sorry, just fell off mny high horse All good now

[tacker]

djr81,

they are cusco neg 5 upper control arms and were about 32,000 yen, i can check on that though. You can get 2.5 as well not going to say where i got them as i got a warning last time i mentioned about a non sponsor but they were from Japan. You can PM me if you would like to know.

[salad]

^^^ If you're gonna spend that sort of money, you may aswell get the adjustable ones from Japan, I got mine second hand for $300AUD delivered friend got the brand new ones for $450 delivered at the same time. Huge scope for adjustment, maxed out at something like 5deg camber at 350mm ride height and can get it back to 1deg easily, havn't tried to see what the minimum is though.

Edited May 17, 2007 by salad

[tacker]

got mine for 320 new and delivered but non adjustable still happy enough with these and the improvement to the cars handling.